BG60602B1 - HERBICIDES AND WEED CONTROL METHOD - Google Patents

Abstract

The herbicidal agent comprises as active ingredient at least one compound of the formula in which: r1 means hydroxy, halogen, cyano, nitro, amino, straight or cyclic alkyl of 1 to 6 carbon atoms, which is optionally substituted halogen, straight chain or branched chain alkoxy group having 1 to 4 carbon atoms, phenoxy group, methylthio or methylsulfonyl group; r2 represents halogen, nitro, methyls, methoxy; n takes values 1 or 2 and m 0 or 1, the sum of n being equal to 1, 2 or 3; r3 means hydroxy or halogen or a group of the formula -octo / o / n / ch3 / 2 or -octo / zr4, in which r4 stands for a straight-chain alkyl group of 3 to 12 carbon atoms, a branched alkyl group of 4 to 7 carbon atoms, cyclohexyl a group, phenylethyl or phenyl; z simple bond, oxygen or sulfur and x halogen, as well as its salts that are physiologically tolerated by the plants.

Description

The invention relates to a herbicide and a method for controlling weeds, which are used in the protection of plant crops in agriculture.

Herbicidally active 3-arylpyridazines are known which have an alkyl or dialkyl or alkylalkoxy or dialkylalkoxyamino group at the 5-position of the pyridazine ring. However, these compounds are intended for use in rice crops and their activity in other fields of application does not give satisfactory results /1/.

Substituted aryl-4/o-acyl/6-halopyridazines are known which have fungicidal activity /2/.

According to the said publication, these compounds are not suitable as herbicidal agents, but only as fungicides.

The object of the invention is to create a herbicidal agent with excellent herbicidal activity in a broad spectrum of application.

The object is achieved according to the invention with a herbicidal composition which contains as active ingredient at least one compound of the general formula I

in which R1 represents a hydroxy, halogen, cyano, nitro, amino group, a straight-chain or cyclic alkyl group of 1 to 6 carbon atoms, which is optionally substituted by halogen, a straight-chain or branched-chain alkoxy group of 1 to 4 carbon atoms, a phenoxy group, a methylthio or methylsulfonyl group;

K ₂ represents a halogen, nitro, methyl or methoxy group, η is 1 or 2, m is 0 or 1, the sum of the letters being equal to 1, 2 or 3,

K ₃ represents hydroxy or halogen, or a group of the formula -OC/O/1H/CH ₃ / ₂ or OC/O/ΖΚ,, in which

K ₄ represents a straight-chain alkyl group of 3 to 12 carbon atoms, a branched alkyl group of 4 to 7 carbon atoms, a cyclohexyl group, phenylethyl or phenyl;

Ζ means a single bond, oxygen or sulfur and

X denotes halogen, as well as its salts physiologically tolerated by plants.

In general formula I, K _] can represent a hydroxy, cyano, nitro, amino group or a halogen atom, in particular chlorine, bromine or fluorine. Furthermore, K _] can represent a straight-chain or cyclic alkyl radical having 1 to 6 carbon atoms, for example a methyl, ethyl, propyl, butyl, pentyl, hexyl radical. These alkyl radicals can be substituted by halogen, for example chlorine, bromine or fluorine, in particular a trifluoromethyl radical. Further in the alkyl chain, K ^ can represent an alkoxy radical having 1 to 4 carbon atoms, for example a methoxy, ethoxy, propoxy, butoxy or phenoxy radical. K1 may also represent a methylthio or methylsulfonyl residue, _K2 represents a halogen, methyl, methoxy or nitro group, η represents one of the numbers 1 or 2, y represents one of the numbers 0 or 1, wherein η+m represents one of the numbers 1, 2 or 3.

Compounds in which K ₁ represents a halogen atom, for example chlorine, bromine or fluorine, or an alkyl radical with 1 to 4 carbon atoms, which is optionally substituted multiple times by halogen, preferably by fluorine, or an alkoxy radical with 1 to 4 carbon atoms in the alkyl chain or a cyclohexyl radical, and K ₂ represents halogen, methyl or methoxy, are preferred.

Particularly preferred are those compounds in which K ₁ and K ₂ represent a halogen atom, for example chlorine or fluorine, where n+m represent 1 or 2, or a trifluoromethyl residue, where n+m represents the number 1, K ₃ represents hydroxy or the residue -ΟΟ/Ο/ΖΚ ₄ , or the residue -ΟΟ/O/14/CH ₃ / ₂ , where K ₄ represents a straight-chain alkyl residue with 3 to 12 carbon atoms, for example methyl, ethyl, propyl or butyl, pentyl, heptyl, decyl, dodecyl or branched alkyl residue with 4 to 7 carbon atoms. In addition, K ₊ can represent a phenyl, phenethyl or cyclohexyl residue.

Preferred are those compounds in which K ₃ represents the residue -OC/O/ZK^, wherein Z and K ₄ have the indicated meanings.

Compounds of formula I can be prepared by:

a/ correspondingly substituted 3-phenyl-pyridazinone-6 of formula II

in which K, K, N have the above meanings and Υ represents hydrogen or chlorine are reacted with a phosphorus oxide halide and in the case where Υ represents hydrogen, additionally with phosphorus or PCl ₃ or PCl ₅ and a halogenating agent until converted into the corresponding dihalogen compound of formula III

b/ optionally this compound is reacted in the presence of a diluent and in the presence of a base to obtain the corresponding 3-phenyl-4-hydroxy-6-halopyridazine of formula IV

OH in which X has the above meanings, after which in/ optionally the compound of formula IV is reacted in the presence of an organic diluent and a base, for example sodium hydroxide, potassium hydroxide, or triethylamine with the corresponding acid halide of formula V or Va,

Hi

wherein K ₄ and Z have the above meanings, to obtain a compound of formula I, in which K ₃ does not represent a hydroxy group or halogen.

In step a) one can start from the corresponding 3-aryl-6-halopyridazine compound.

If K or _K2 represents a nitro group, this can optionally be introduced before carrying out step c) by nitration of the corresponding 3-aryl-4-hydroxy-6-halopyridazine compound. However, it is possible to use a correspondingly substituted pyridazinone-6 in step a).

The substituted 3-phenylpyridazinone-6 compounds required as starting compounds are prepared in a known manner from the corresponding acetophenones by reaction with glyoxylic acid and hydrazine or from the corresponding benzoylacrylic acid by reaction with a lower aliphatic alcohol in the presence of a catalyst and subsequent reaction with hydrazine or from the corresponding benzoylacrylic acid by esterification with a lower aliphatic alcohol in the presence of an esterification catalyst and subsequent reaction with hydrazine, respectively by reaction of the corresponding benzoylacrylic acid with _NH3 and hydrazine.

The preparation of the compound of formula II, in which Y is Cl, can be carried out according to Weilberg A., Taury E. C. (Heinrich), The Chemical Synthesis of Heinrich Sociology, Vol. 28, p. 32. The conversion to dihalogen compounds is carried out in the presence of a phosphorus oxyhalide and, if Y is H, additionally reacted with phosphorus or PCl ₃ or PCl ₅ and a halogenating agent. The dihalogen compounds are then optionally converted in the presence of a diluent, for example dioxane/water tetrahydrofuran and the like, and in the presence of a base, for example an alkaline base such as sodium or potassium base, into compounds of formula IV.

The optional subsequent acylation by conversion with an acid chloride of formula V or Va is carried out in the presence of an organic diluent, for example in aqueous acetone, toluene or benzene and the like, and in the presence of a base. As bases, inorganic bases such as sodium or potassium bases or organic bases such as triethylamine can be used.

The preparation of the amino salts of the hydroxy compounds of formula I, in which _K3 =OH, is conveniently carried out directly in a suitable formulation medium with the addition of a wetting agent. For example, a 50% preparation of the triethylammonium salt of a compound of formula I, in which K1 =4Cl, _K2 =H, _K3 =OH, X-Cl, is prepared by suspending the hydroxy compound (substance I, 3.526 g, 0.0146 mol) in a mixture of glycerol (4.445 g) and Rapidumwetting agent-Linz (0.500 g) and then slowly adding triethylamine (1.527 g, 0.01509 mol, 3.2% excess). The mixture is then heated slowly over a period of 2 h, during which the temperature is raised from 40°C to 60°C.

This produces a homogeneous 50%, ready-to-use mixture of the triethylammonium salt.

The agents according to the invention are suitable for controlling not only monocotyledonous but also dicotyledonous weeds in crops such as cereals, corn, peanuts, cabbage species, peas, tomatoes and onions.

They are particularly suitable for combating:

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8»che11apa tesYaa in the above-cited cultivated plants.

The compositions according to the invention can be formulated in the usual manner, for example as solutions, wettable powders, emulsion concentrates, emulsions, suspensions, dispersions, dusting powders, granules, etc., and optionally contain the usual formulation auxiliaries, for example liquid solvents, liquid or solid carriers, optionally surface-active substances such as emulsifiers and/or dispersants and/or wetting agents, grinding aids, adhesives, etc. If water is used as a diluent, organic solvents can also be used to aid dissolution. Liquid solvents include, in particular: aromatic substances such as xylene, toluene and other alkylbenzenes or alkylnaphthalenes, chlorinated aromatic or chlorinated aliphatic hydrocarbons such as chlorobenzene, chloroethylene or methylene chloride, cycloaliphatic hydrocarbons such as cyclohexane or paraffins, e.g. petroleum fractions, alcohols such as butanol or glycol, as well as their ethers and esters, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone or cyclohexanone, highly polar solvents such as dimethylformamide or dimethyl sulfoxide, and water.

Wettable powders are preparations which are uniformly dispersed in water and which may contain, in addition to the active substance, optionally diluents or inert substances, also wetting substances, for example polyoxyethylated alkylphenols, polyoxyethylated oleyl or stearylamines, alkyl or alkylphenyl sulfonates and dispersants, such as Nβoleylmethyltauride, lignin sulfonates or condensation products of aryl sulfonates with formaldehyde.

Emulsifiable concentrates can be prepared, for example, by diluting the active ingredient with an organic solvent by adding one or more emulsifiers. Nonionic or ionic surfactants can be used as emulsifiers, for example, such as polyoxyethylene sorbitan tall oil esters, polyoxyethylene fatty acid esters, polyoxyethylene fatty alcohol ethers, alkylaryl polyglycol ethers, alkyl sulfonates, alkyl sulfates and alkyl aryl sulfonates, and protein hydrolysates.

Dusting agents are obtained by grinding the active ingredient with finely divided solids, such as natural mineral flours, for example kaolins, clays, talc, chalk, quartz, attapulgite, montmorillonite or diatomaceous earth, or with synthetic products, such as highly dispersed silicic acid, alumina and silicates.

Suitable carriers for granules are, for example, crushed or ground natural minerals such as calcite, marble, pumice, sepiolite, dolomite, as well as synthetic granules of inorganic or organic flours, as well as granules of organic materials such as shavings from coconut shells, from corn cobs and from tobacco plant stems. Adhesives and thickeners such as carboxymethylcellulose, methylcellulose, natural and synthetic powdered, granular and latex-like polymers such as gum arabic, polyvinyl alcohol, polyvinyl acetate can also be used in the formulations.

Colorants such as organic pigments, for example, mulberry oxide, titanium oxide, ferrocyanide blue, and organic dyes such as alizarin, phthalocyanine dyes, etc. can be used.

In general, the formulations contain between 0.1 and 95% by weight of active ingredient, preferably between 0.5 and 90% by weight.

The active substances can be applied as they are, in the form of preparations, which are further diluted to working solutions and thereby ready-made solutions, emulsions, suspensions, powders or granules are obtained. The application is carried out in the usual ways, for example by watering, spraying, in the form of fog, by dusting, sprinkling, etc.

The application rates (consumption rates) vary depending on external conditions such as temperature, humidity, etc. They can vary within wide limits and generally amount to 0.2 and 10 kcal/l of active substance, preferably 0.3 to 1.5 kcal/l.

Example 1. Preparation of the starting compound 3-(4'-fluorophenyl)-pyridazinone-6.

a) From p-fluoroacetophenone with glyoxalic acid and hydrazine:

4'-Fluoroacetophenone (138.1 g, 1 mol) and glyoxylic acid monohydrate (27.5 g, 0.3 mol) were mixed and stirred at 105°C for 1.75 h. The reaction mixture was then cooled to 60°C and partitioned between water (500 ml) and Inhibisol (400 ml), the pH of the aqueous phase being adjusted to 9 with ammonia solution. The separated layers were then washed once more with Inhibisol (200 ml) and then with very dilute ammonia solution (pH 9, 400 ml) and the combined aqueous portions (pH about 8.5) were mixed with hydrazine hydrate (16.5 g). Boil 4 l under reflux, concentrate (400 ml distillate), cool to 0°C and the separated crystals are isolated. Wash with water and dry to constant weight. 3-(4'fluorophenyl)-pyridazinone-6 (48.0 g, 0.2524 mol, 84.5% of theoretical yield) is obtained with mp 264-269°C. After recrystallization from a mixture of dimethylformamide-ethanol the compound has mp 268-270°C.

b) From (4'-fluorobenzoyl)-acrylic acid:

(4'-Fluorobenzoyl)-acrylic acid (582 g, 2.998 mol, mp 134-137°C) was dissolved in ethanol (3300 ml) and p-toluenesulfonic acid (23 g) and sulfuric acid (concentrated, 4 ml) were added to the solution, after which the mixture was refluxed at 18 K. The mineral acid was neutralized by adding anhydrous sodium bicarbonate. The inorganic salts were filtered off and a hydrazine solution (6 mol hydrazine, 700 ml water) was added to the solution of the ester product with mechanical stirring and the reaction mixture was refluxed for 3 h. A solid product is separated, which is isolated, washed with water and to it, as it is wet after the suction, dilute hydrochloric acid (700 ml! concentrated hydrochloric acid, 1600 ml! water) is added and 2 l is refluxed. It is cooled and the separated solid product is isolated, washed with water and dried to constant weight. 3-(4'fluorophenyl) -pyridazinone-6 is obtained in the form of a yellowish solid product (390 g, 2.0508 mol, 68.4% of theory) with mp. 266-269 ° C.

After recrystallization from dioxane, an almost colorless product is obtained, which sublimes at about 170°C into wide crystals and melts at 269-270.5°C.

c) from (4'-fluorobenzoyl)alanine:

3-(4'-fluorobenzoyl)-acrylic acid (9.7 g, 0.04996 mol) was dissolved in 50 ml of concentrated aqueous ammonia solution and the solution was left for several days in the open air.

Initially neutralized by adding hydrochloric acid (concentrated, 30 ml), then another 20 ml of concentrated hydrochloric acid were added and then hydrazine hydrochloride (4.1 g, 0.06 mol). The mixture was refluxed for 8 hours. After cooling, a solid product separated, which was isolated, washed with water and dried to constant weight. 3-(4-fluorophenyl)-pyridazinone6 was obtained with mp 265-267°C, 8.9 g, 0.04680 mol. This corresponds to a 93.7% yield of the theoretical.

Example 2. Compound No. 68 3-(4'-fluorophenyl)-4,6-dichloropyridazine

3-(4'-Fluorophenyl)-pyridazinone-6 (190 g, 0.9991 mol) was mixed with red phosphorus (40 g, 1.291 mol) and 1300 ml of phosphorus oxychloride were added to the mixture. Over 1 h, the temperature of the suspension was raised to 90°C and a medium stream of chlorine was passed through the solution. The temperature of the reaction mixture was raised to 100°C and the mixture was maintained at this temperature. Chlorination was carried out with 4 N and then the dissolved gases were purged by introducing a medium stream of nitrogen. Under a vacuum obtained from a water pump, 800 ml of phosphorus oxychloride were distilled off and decomposed on ice. The acid formed was neutralized with concentrated ammonia solution to give 235.2 g (0.9676 mol) of 3-(4'-fluorophenyl)-4,6-dichloropyridazine as a solid, corresponding to a 96.9% yield of crude product. Recrystallization from ethanol and cyclohexane gave a product melting at 124-127°C.

Example 3. (Compound No. 56) 3-(4'-fluorophenyl)-4-hydroxy-6-chloropyridazine

3-(4'-Fluorophenyl)-4,6-dichloropyridazine (145.84 g, 0.600 mol) was dissolved in dioxane (800 ml) at 60°C, water (300 ml) was added and the solution was refluxed. Sodium hydroxide solution (48 g HONH dissolved in 300 ml water) was added dropwise over 1/2 l and the mixture was kept at reflux for another 5 l. The reaction mixture was distilled to dryness under vacuum and the residue was dissolved in hot water (5 l). The undissolved residues were filtered off and the pH was adjusted to 1 with concentrated hydrochloric acid. The separated solid phase was isolated, washed with water and, for further purification, dissolved in dilute ammonia (8 l water, pH 9-10). By careful addition of hydrochloric acid, small amounts of 3-(4'-fluorophenyl)-4-chloropyridazinone-6 were selectively separated, which were filtered off and then most of the compound precipitated (to pH 1). The resulting solid product was isolated, washed with water and dried to constant weight. 91.0 g (0.4051 mol) of 3-(4'-fluorophenyl)-4-hydroxy-6-chloropyridazine with a melting point of 254-260°C were obtained, which corresponds to 67.5% of the theoretical yield.

Example 4. (Compound No. 64) 3-(4'-fluorophenyl)-6-chloro-4-(octylthiocarbonyloxy)pyridazine

3-(4'-Fluorophenyl)-4-hydroxy-6-chloropyridazine (22.5 g, 0.1 mol!) was suspended in 80 ml of acetone. A solution of 4 g (0.1 mol) of sodium hydroxide in 80 ml of water was added to it and the initially cloudy solution was heated to 60°C. To the thus obtained clear solution was added octylthioester of chloroformic acid (20.97 g, 0.1 mol). As the reaction proceeded, the solution heated and an emulsion formed. The reaction mixture was kept at reflux for 3/4 l and the pH, which had dropped to 6, was adjusted to 9 with 25% sodium hydroxide solution. The heavier organic layer of the resulting two-phase mixture was separated and freed from volatile components under vacuum. The resulting crude ester (brown oil, 36.7 g, 95% crude yield) was purified through a silica gel column to yield the above compound as a yellow oil (n ²⁰ =1.5567, 30.4 g, 79% of theory).

Example 5. Compound No. 57.3-(4'-fluorophenyl)-4-(propylthiocarbonyloxy)-6-chloropyridazine

3-(4'-Fluorophenyl)-4-hydroxy-6-chloropyridazine (22.4 g, 0.1 mol) was suspended in benzene (2000 ml) with stirring, triethylamine (10.1 g, 0.1 mol) was added and the mixture was stirred for 3.5 h at room temperature. Propylthiol chlorocarbonic acid ester (13.86 g, 0.09999 mol) was added dropwise to the mixture over 10 h. A slight warming occurred and the reaction mixture was stirred for a further 3 h without further heating. The separated triethylaminohydrochloride was filtered off and the benzene phase was washed successively with 2 x 100 ml of water, with very dilute hydrochloric acid, with very dilute sodium hydroxide and then again with water. The organic phase is dried over sodium sulfate, purified over charcoal and the solvent is completely removed by distillation under vacuum, finally under vacuum, obtained with an oil pump and at a bath temperature of 90° C. 27.0 g (0.08263 mol) of 3-(4'-fluorophenyl)4-(propylthiocarbonyloxy)-6-chloropyridazine are obtained in the form of a yellow oil, which corresponds to a yield of 82.9% of theory.

Example 6. (Compound No. 143). 3-(4'Bromophenyl)-4-(2,2-dimethylpropyloxycarbonyloxy)-6-chloro-pyridazine.

3-(4'-Bromophenyl)-4-hydroxy-6-chloropyridazine (prepared analogously to Examples 1-3) (8.57 g, 0.03 mol) was suspended in benzene (90 ml) and triethylamine (3.19 g) was added. A noticeable change in the solid occurred. The mixture was stirred for 30 min and then a solution of 2,2-dimethylpropyl chloroformate (4.38 g, 0.0291 mol) in 20 ml of benzene was added dropwise over 30 min. The mixture was warmed slightly. After 3 K, water (20 ml) was added, the mixture was stirred vigorously for 5 min and the benzene layer was separated. It was dried over sodium sulfate and the solvent was removed in vacuo. The residue solidified and was recrystallized twice from diisopropyl ether. 3-(4'-bromophenyl)-4-(2,2-dimethylpropyloxycarbonyloxy)-6-chloropyridazine was obtained in the form of colorless crystalline prisms with mp 114-116°C (6.7 β, 0.01676 mol, 57.6% of theory).

Example 7. (Compound No. 19). 3-(4'-Chlorophenyl)-4,6-dibromopyridazine

3-(4'-Chlorophenyl)-4-hydroxy-6-chloropyridazine (compound I, 24.1 g, 0.09997 mol) was placed in a flask and a solution of phosphorus oxybromide (85.8 g, 0.3 mol) in toluene (150 mol) was added, after which the reaction mixture was stirred at room temperature for 1 l. At gentle reflux, the mixture was heated to 3 N, during which hydrogen bromide gas was released. It was decomposed on ice, resulting in a mushy mass, which crystallized upon trituration with petroleum ether. The product was washed well with water, isolated and dried to constant weight. 30.0 g (0.0861 mol, 86.1% of theoretical yield) of 3-(4-chlorophenyl)-4,6-dibromopyridazine with a m.p. 160-162°C. A sample recrystallized from a mixture of ethanol-dioxane (20+3) had a mp of 163-165°C.

Example 8. (Compound No. 16). 3-(4'-Chlorophenyl)-4-hydroxy-6-bromopyridazine

3-(4'-chlorophenyl)-4,6-dibromopyridazine (52.2 g, 0.1498 mol) was dissolved in dioxane (300 ml) while hot and, while gently refluxing, a solution of 12 g (0.3 mol) of sodium hydroxide in 50 ml of water was added dropwise over 10 min. The boiling was maintained for another 4.5 min, after which the dioxane was evaporated under vacuum and the resulting solid residue was dissolved in 1 l of hot (95°C) water. The small amount of solid product (tar-like) was filtered off while hot through charcoal and the hydrolysis product was precipitated with hydrochloric acid. The isolated solid product, as wet after the extraction, was stirred in 1 l of water and the pH of the suspension was adjusted to 9-10 at 65°C with ammonia. Most of the product dissolved, the undissolved part was isolated and treated again with ammonia. The combined filtrates were then acidified with hydrochloric acid and the precipitated 3-(4'chlorophenyl)-4-hydroxy-6-bromopyridazine was isolated, washed with water and dried to constant weight. This gave 27.5 g (0.09631 mol), which is 64.3% of the theoretical yield. M.p. 262-264'C.

Example 9. (Compound No. 17)

3-(4-chlorophenyl)-4-(butylthiocarbonyloxy)-6-bromopyridazine

3-(4'-Chlorophenyl)-4-hydroxy-6-bromopyridazine (14.2 g, 0.0497 mol) was suspended in benzene (100 ml), triethylamine (5.5 g, 0.0543 mol) was added and the reaction was allowed to proceed to completion, the mixture was stirred at room temperature for 3.5 h. Then, 5-butylthioester of chlorocarbonic acid (7.85 g, 0.05162 mol) was added dropwise to the mixture over 5 h and the reaction mixture was stirred for another 3 h without heating. The separated triethylamine hydrochloride was filtered and the benzene solution was washed successively with 150 ml portions of water, strongly diluted hydrochloric acid, strongly diluted sodium hydroxide and again with water and dried over sodium sulfate. The solvent was then completely removed, initially under vacuum, finally with an oil pump vacuum (0.2 Torr, 90°C bath temperature). The initially obtained oily 5-butylthiocarbonate of 3-(4'-chlorophenyl)-4-hydroxy-6-chloropyridazine, 17.5 g, 0.04356 mol, 87.6% of theoretical yield, solidified on longer standing and recrystallized from hexane had a mp of 68-71°C.

Example 10. (Compound No. 138)

3-(3'-nitro-4'-chlorophenyl)-4-hydroxy6-chloropyridazine

3-(4'-Chlorophenyl)-4-hydroxy-6-chloropyridazine (12 g, 0.04978 mol) was added over 15 min at 0°C in cooled, highly concentrated nitric acid. The mixture was then stirred for a further 30 min at 0°C and the reaction mixture was poured into ice water. The resulting yellow solid was isolated, washed with water and recrystallized with 1CH ₄ OH/HCl. After drying, 11 g, 0.0385 mol of 3-(3'-nitro-4'-chlorophenyl)-4-hydroxy-6-chloropyridazine with a melting point of 204-209°C was obtained, which corresponds to 77.25% of the theoretical yield of crude product. A sample of the product, after thin layer chromatography (silica/10% ethanol-chloroform), was found to be substantially pure. After recrystallization from ethanol, the compound melted at 208-211°C.

3-(3'-Nitro-4'-chlorophenyl)-4-butylthiocarbonyloxy)-6-chloropyridazine (compound #88)

3-(3'-Nitro-4'-chlorophenyl)-4-hydroxy-6-chloropyridazine (14.3 g, 0.05 tol!) was reacted in benzene in the usual manner with chloroformic acid butylthioester (7.88 g) and triethylamine (5.05 g), as a hydrogen chloride acceptor. 3-(3'-nitro-4'-chlorophenyl)-4-(butylthiocarbonyloxy)-6-chloropyridazine was obtained as a light yellow oil, 17.0 g, 0.04226 tol, 84.55% of theoretical yield, η ²⁰ =1.6073.

Examples

Examples: K, K, η sh Kz X T.p. (0C)/p _o ²⁰ 1 4-C1 - 1 - OH C1 264-268* 2 4-C1 - 1 - OS(O)S ₇ H ₁₅ -P C1 40-43.5 3 4-C1 - 1 - ΟΟ(Ο)Ν(ΟΗ ₃ ) ₂ C1 70-82 4 4-C1 - 1 - OC(O)OCH ₂ CH(CH ₃ ) ₂ C1 72-74 5 4-C1 - 1 - O(CO)OSdNdd-P C1 6 4-C1 - 1 - OS(O)ZS ₃ H ₇ -P C1 39-45 7 4-C1 - 1 - 0С(О)ЗС ₄ Н ₉ -н C1 77.5-80 8 4-C1 - 1 - OS(O)ZS ₄ H ₉ -Y C1 120-123 9 4-C1 - 1 - OS(O)zs ₅ n ₁₁ -p C1 32-38 10 4-C1 - 1 - OS(O)5S _b H ₁₃ -p C1 11 4-C1 - 1 - OS(O)ZS ₇ H ₁₅ -P C1 12 4-C1 - 1 - OS(O)ZS ₈ H ₁₇ -P C1 1.5733 13 4-C1 - 1 - OS(O)ZS ₁₂ H ₂₅ -P C1 14 4-C1 - 1 - 0С(0)ЗС _b N _g1 -С C1 15 4-C1 - 1 - OS(O)ZS _b H ₅ C1 105-108 16 4-C1 - 1 - OH Cg 262-264 17 4-C1 - 1 - OS(O)ZS ₄ H ₉ -P Cg 68-71 18 4-C1 - 1 - OS(O)ZS ₈ H ₁₇ -P Cg 19 4-C1 - 1 - Cg Cg 163-165 20 4-Cg - 1 - OH C1 271-276 21 4-Cg - 1 - OS(O)(CH ₂ ) ₅ CH ₃ c1 22 4-VG * 1 - OC(O)CH ₂ CH(CH ₃ ) ₂ C1 49-56 23 4-Cg - 1 - OS^SdN^-P C1 24 4—Cg - 1 - OS(O)ZS ₃ H ₇ -p C1 75-77 25 4-Cg - 1 - 0C(0)ZC ₄ H ₉ -zes C1 71-73 26 4-Cg - 1 - OS(O)ZS ₄ H ₉ -G C1 121-124 27 4-Cg - 1 - OS(O)ZS ₅ H ₁₁ -P C1 57-59 28 4-VG - 1 - OS{O)ZS ₅ H ₁₁ -1 C1 72-74 29 4-Cg - 1 - os(o)zs ₅ n ₁₁ -e C1 75-88 30 4-Cg - 1 - OS(O)ZS ₇ H ₁₅ -P C1 63-65 31 4-VG - 1 - OS(O)ZS ₈ H ₁₇ -P C1 45-47 32 4-VG - 1 - OS(O)ZS ₁₀ H ₂₁ -η C1 51-54 33 4-VG - 1 - OS(O)5C ₆ H ₁₁ -s C1 69-73 34 H-Cg - 1 - C1 c1 112-114

h-vg — 1 - he C1 208-212 H-VG - 1 - OC(O)CH(C ₂ H ₅ )C ₄ H ₉ C1 1.5680(P ₀ ²⁵ h-vg - 1 - OS(O)OS ₄ H ₉ -1 C1 1.5795(P _O ²⁵ H-Cg - 1 - OS(O)5C ₄ H ₉ -n C1 1.6080(n ₀ ²⁵ h-vg - 1 - OS(O)5C ₄ H ₉ -3 C1 1.6085(n ₀ ²⁵ h-vg - 1 - OS(O)ZS ₈ H ₁₇ -P C1 1.5792(P _O ²⁵ 4-CH ₃ O - 1 - he C1 245-247 4-CH ₃ O - 1 - OS(O)S _b H ₁₃ -p C1 1.5598 4-CH ₃ O - 1 - OS(O)S ₇ H ₁₅ -p C1 1.5539 4-CH ₃ O - 1 - OS(O)OS ₄ H ₉ -1 C1 58-59.5 4-CH ₃ O - 1 - OS(O)OS ₅ H ₁₁ -P C1 1.5677 4-CH ₃ O - 1 - (OS(O)ZS ₄ H ₉ -P C1 44-53 4-CH ₃ O - 1 - C1 C1 144-147 Sun-Wed ₃ - 1 - OH C1 238-240* Sun-Wed ₃ - 1 - OS(O)(CH ₂ ) ₅ CH ₃ C1 1.5162 Sun-Wed ₃ - 1 - OS(O)(CH ₂ ) _b CH ₃ C1 1.5145 Sun-Wed ₃ - 1 - ΟΟ(Ο)ΟΟ ₄ Η ₉ -ί C1 45-48.5 Sun-Wed ₃ - 1 - OS(O)OS ₅ H ₁₁ -P C1 1.5161 Sun-Wed ₃ - 1 - OS(O)ZS ₄ H ₉ -P C1 36-40 Sun-Wed ₃ - 1 - OS(O)ZS ₈ H ₁₇ -p C1 1.5323 Sun-Wed ₃ - 1 - C1 C1 80-81.5 4-P - 1 - he C1 254-260* 4-P - 1 - OS(O)ZS ₃ H ₇ -P C1 4-D - 1 - OS(O)ZS ₄ H ₉ C1 4-P - 1 - OS(O)ZS ₄ H ₉ -3 C1 4-P - 1 - OS(O)ZS ₄ H ₉ -1: C1 109-111 4-P - 1 - OS(O)ZS ₅ H _and -1 C1 4-P - 1 - axis(O)axis ₅ n ₁₁ -1: C1 65-68 4-P - 1 - 0C(0)ZC ₇ H ₁₅ -P C1 4-P - 1 - 0C(0)ZC ₈ H ₁₇ -P C1 1.5567 4-P - 1 - OS(O)ZS ₁₂ H ₂₅ -P C1 33-36 4-P - 1 - OS(O)5C _b H ₁₁ -C C1 57-59 ⁴ ~ ^C 2 ^H 5 - 1 - OH C1 224-225 4-P - 1 - C1 C1 124-127 4-C1 2-C1 1 1 OH C1 233-237* 4-C1 2-C1 1 1 OS(O)ZS ₄ H ₉ -P C1 4-C1 2-C1 1 1 C1 C1 144-147 4-C ₂ H ₅ - 1 - OS(O)ZS ₈ H ₁₇ C1 1.5637

4-C1 3-C1 1 1 OS(O)OSH ₂ C(CH ₃ ) ₃ C1 109-111.5 4-C1 3NO ₂ 1 1 OS(O)5S ₈ H ₁₇ -P C1 1.5821 4-VG 3NO ₂ 1 1 OH C1 209-212 4-C ₂ H ₅ 1 - OS(O)ZS ₄ H ₉ -p C1 4-C1 3-C1 1 1 OH C1 239-243 4-C1 3-C1 1 1 OC(O)CH ₂ CH(CH ₃ ) ₂ C1 48-52 4-C1 3-C1 1 1 OS(O)ZS ₃ H ₇ -P C1 1.6186 4-C1 3-C1 1 1 OS(O)ZS ₄ H ₉ -P C1 1.6108 4-C1 3-C1 1 1 OS(O)ZS ₈ H ₁₇ -P C1 1.5814 4-VG 3NO ₂ 1 1 OS(O)ZS ₄ H ₉ C1 1.6199 4-CH ₃ 1 - OH C1 240* 4-CH ₃ 1 - OS(O)ZS ₄ H ₉ -P C1 4-CH ₃ ZSN ₃ 1 1 OS(O)OS ₄ H ₉ -1 C1 4-CH ₃ 5 1 - OS(O)OS ₅ N _X1 -n C1 65-66.5 4-CH ₃ 5 1 - OS(O)ZS ₄ H ₉ -P C1 1.6332 4-C1 3NO ₂ 1 1 OS(O)ZS ₄ H ₉ -p C1 1.6073 4-VG 3NO ₂ 1 1 0C(O)0C ₇ H _X 5-P C1 69-72 4-VG 3NO ₂ 1 1 OS(O)OS ₄ H ₉ -1 C1 1.5942 4-CH ₃ 2CH ₃ 1 1 C1 C1 92-100 4(5)NO ₂ 2(3)NO ₂ 1 1 OC(O)OCH ₂ CH(CH ₃ ) ₂ C1 - 4-C1,3-C1 2-C1 2 1 OH C1 230-237 4-C1,3-C1 2-C1 2 1 OS(O)ZS ₄ H ₉ -P C1 4-C ₄ H ₉ 0 1 - OS(O)(CH ₂ ) ₅ CH ₃ C1 4-CH ₃ O 3NO ₂ 1 1 C1 C1 213-215 4-S _b H ₅ O 1 - OH C1 197-201* 4-C ₆ H ₅ O 1 - OS(O)OS ₃ H ₁₁ -P C1 1.5901 4-S _b H ₅ O 1 - OS(O)ZS ₄ H ₉ -P C1 1.6179 4- VG 3NO ₂ 1 1 OS(O)ZS ₈ H ₁₇ -P C1 1.5895 5-C1 2-C1 1 1 0С(О)ЗС ₄ Н ₉ -н C1 4-P 1 - OS(O)ZS ₅ N _X1 -P C1 4-VG 3NO ₂ 1 1 OC(O)CH(C ₂ H ₅ )C ₄ H ₉ C1 69-72 4-CH ₃ 3 1 - OH C1 230-231 4-CH ₃ 5O ₂ 1 - OH C1 203-212 4-CH ₃ 3 1 - C1 C1 120-121 2-CH ₃ 5CH ₃ 1 1 C1 C1 100-101 4(5)ΝΟ ₂ 2{3)ΝΟ ₂ 1 1 OH C1 250-252 4(5)NO ₂ 2(3)NO ₂ 1 1 OS(O)OS ₅ H _1X C1 4(5)NO ₂ 2(3)NO ₂ 1 1 OS(O)M(CH ₃ ) ₂ C1

111 401,301 2C1 2 1 C1 C1 115-118 112 4-C ₄ H ₉ O 1 - OS(0)5C _b H ₁₁ -C C1 1.5882 113 4-C ₄ H ₉ O 1 - OS(O)ZS ₈ H ₁₇ -P C1 50-53.5 114 4-C ₄ H ₉ O 1 - OS(0)5C ₁₂ H ₂₅ -P C1 50-56 115 4-C ₄ H ₉ O 1 - ΟΟ(Ο)Ν(ΟΗ ₃ ) ₂ C1 97.5-99 116 4-C ₄ H ₉ O 1 - C1 C1 62-63 117 4-CH ₃ O 3NO ₂ 1 1 he C1 250-254* 118 4-S _b H ₅ O 1 - C1 C1 129-133 119 3-η ₂ 1 - he C1 185-188 120 4-SvHc-S 1 - he C1 225-235 121 h-sn ₃ 4CH ₃ 1 1 he C1 222-224 122 4-C ₂ H ₅ 1 - OC(0)OCH ₂ C(CH ₃ ) ₃ C1 70-71.5 123 h-sn ₃ 4CH ₃ 1 1 OS(O)S ₅ N _p -P C1 124 h-sn ₃ 4CH ₃ 1 1 C1 C1 90-92 125 3-C1 4C1 1 1 C1 C1 150-152 126 4-CH ₃ -5O ₂ 1 - 0C(0)ZC ₄ H ₉ “P C1 99-102 127 5-CH ₃ 2CH ₃ 1 1 he C1 163-170 128 4(5)MO ₂ 2(3)NO ₂ 1 1 C1 C1 161-166 129 401,301 2C1 2 1 OS(O)ZS ₈ H ₁₇ -P C1 130 4-C ₄ H ₉ O 1 - he C1 216-218 131 4-C ₄ H ₉ O 1 - OS(O)OSdN^u-P C1 37-39 132 4-C ₄ H ₉ O 1 - OS(O)OS ₄ H ₉ -1 C1 68-70 133 4-C ₄ H ₉ O 1 - 00(0)50^-11 C1 52-54 134 3MO ₂ 5NO ₂ 4CH ₃ O 2 1 he C1 280 135 4-S _b Nc-S 1 - 00(0)50^-11 C1 1.5878 136 ^{4 s} b ⁿ 11 ^s 1 - C1 C1 115-118 137 4C1 1 - 0C(0)3CH ₂ CH ₂ C _in H ₅ C1 1.6303 138 4-C1 3NO ₂ 1 1 he C1 208-211 139 No. ₂ 1 - C1 C1 186-191 140 No. ₂ 1 - he C1 246-249 141 h-ko ₂ 1 - 0С(0)0С ₅ H ₁ ^-P C1 142 4—OH 1 - he C1 280* 143 4-Cg 1 - 0С(0)0СН ₂ С(СН ₃ ) ₃ C1 114-116 144 4-ON 1 - C1 C1 210-222 145 4-ON 1 - OH C1 286-290

*-with decomposition

Example A.

parts of compound No. 9 are melted and in a liquid state are well homogenized with 20

h. precipitated and ground silicic acid, 50 h. kieselguhr, 3 h. N-salt of diisobutylnaphthalenesulfonic acid and 7 h. Na-ligninsulfonate and ground in a planetary mill for 1 hour. A wettable powder is obtained, which is easily dispersed in water and is suitable for dilution, thereby obtaining a biologically active working solution suitable for spraying.

Example B.

parts of compound No. 57, a light brown oil, is mixed well with 40 parts of precipitated, ground silicic acid, 10 parts of kieselguhr, 4 parts of chalk, 3 parts of diisobutyl-naphthalenesulfonic acid No. salt and 3 parts of Na-HCl-oleoyl-N-methyltauride and ground for 1 hour in a planetary ball mill. A wettable powder is obtained, which is easily dispersed in water and is therefore suitable for preparing a biologically active working solution.

Example C.

parts of compound No. 19 are mixed well with 10 parts of precipitated ground silicic acid, 10 parts of ataclay, 2 parts of diisobutylnaphthalenesulfonic acid salt, 1 part of N-oleyl-N-methyltauride and 7 parts of Ka-ligninsulfonate and ground for 1 hour in a planetary ball mill. A wettable powder is obtained, which is easily dispersed in water and is therefore suitable for preparing a biologically active working solution.

Example ϋ.

parts of compound No. 36 are mixed well with 45 parts of precipitated ground silicic acid, 2 parts of Nλ-salt of diisobutylnaphthalenesulfonic acid and 3 parts of Ia-M-oleyl-M-methyltauride and 1 part is ground in a planetary ball mill. A wettable powder is obtained, which is easily dispersed in water and is suitable for preparing a biologically active working solution.

Example E.

parts of compound No. 64 are mixed well with 45 parts of precipitated ground silicic acid, 9 parts of finely ground chalk, 3 parts of Ia-salt of diisobutyl-naphthalenesulfonic acid and 3 parts of Ia-M-oleyl-M-methyltauride and 1 part is ground in a planetary ball mill. A wettable powder is obtained, which is easily dispersed in water and is suitable for preparing a biologically active working solution for spraying.

Example E.

parts of compound No. 53 are dissolved in 65 parts of Solveso 100 (an aromatic solvent consisting mainly of trimethylbenzenes) and 10 parts of an emulsifier mixture consisting of calcium dodecylbenzenesulfonate and tall acid polyoxyethylene sorbitan ester are added to the solution. An emulsifiable concentrate is obtained, which is suitable for the preparation of a biologically active working solution.

Example C.

parts of compound No. 52 are dissolved in a mixture of 20 parts xylene and 10 parts butyrolactone and 10 parts of an emulsifier mixture consisting of calcium dodecylbenzenesulfonate and polyoxyethylene-sorbitan ester of tall acid are added to the solution. An emulsifiable concentrate is obtained, which is suitable for preparing a biologically active working solution.

Example N.

parts of compound No. 64 are dissolved in a mixture of 30 parts of Solveso 100 and 20 parts of cyclohexanone and 10 parts of an emulsifier mixture consisting of calcium dodecylbenzenesulfonate and polyethoxylated castor oil are added to the solution. An emulsifiable concentrate is obtained, which is suitable for preparing a biologically active working solution.

Example I.

parts of compound No. 22 are dissolved in 80 parts of Solveso 100 and 10 parts of an emulsifier mixture consisting of calcium dodecylbenzenesulfonate and polyethoxylated nonylphenol are added to the solution. An emulsifiable concentrate is obtained, which is suitable for preparing a biologically active working solution.

Example I. Herbicidal activity

The application is carried out with a certain amount of active substance (see the individual amounts used in the experiments) using the “post-emergence” method (3-5 leaf stage of the experimental plants).

The evaluation of the experimental results is carried out according to the scheme given in Table 1.

The trials were visually scored 2-3 times (scale 1-9). The results given are averages of all readings. The codes of the individual trial plants are given in Table 2.

TABLE I

Rating scheme on a scale from I to 9

Rating Herbicidal activity in % I excellent 100 2 very good 97.5 3 good 95.0 4 satisfactory 90.0 5 still enough 85.0 6 is not enough 80.0 7 small 75.0 8 very small 65.0 9 no activity 32.5

TABLE 2 Code Code of the experimental plants used Latin name AMANE AtagapЮiz ge1: oPihiv ANTAN Ap^ЬetЬv aguepaЬa ΟΕΝΑΗ SepHaigea apgep81a SNER1 SЬeporosPit PsЬGoNit BSNSO Esb1posb1oa sgi8-£a111 OAP OaNit arag!pe WITH ME Megsig1a1a appia BARSO Ьaraapa sottshIa RANMI Rapsit tNNaseit ZETOĐ ZeXarbia e1aisa ZO'AM ZoЬpit ategЬsapit THEOIiNI 5о1апит п±8гит TOPIC The (Pa

Standard: 6-Chloro-3-phenylpyridazin-4-yl-5-octylthiocarbonate AB - active substance a) Nopon (oil additive)

Example K

Compound- Norma β AB/bA Herbicidal activity according to Medium SAYAAR scale from 1 to 9 TOPIC BARSO ANTAK benchmark 300 1.7 4.3 1.7 1.7 2.35 standard+a 300+5.0 1 1.7 5.0 1.7 1.3 2.42 cont.64 300 1.3 3.3 1.7 1.3 1.9 Union 64+a 300+5.0 I 1.0 2.3 1.7 1.3 1.58

In this experiment, the tested compound Similar results for their activity are obtained from analogous compounds. Example b. has better activity Example b from the standard used. Sayed- Norma Herbicidal activity according to nenie β AB/bа scale from 1 to 9 ZOM SNER1 MEKAN AMAKE Medium

benchmark 300 1.0 1.0 3.0 1.5 1.63 benchmark 150 1.0 1.0 4.0 2.0 2.0 cont.64 300 1.0 1.0 2.0 1.5 1.38 cont.64 150 1.0 1.0 2.0 1.5 1.38

Analogous compounds give similar herbicidal activity.

Example M

Compound - Product k§/b

Herbicidal activity according to a scale of 1 to 9

SAЬAR ΞΤΕΜΕ ЬАРСО ΑΝΤΑΚ Average

benchmark 0.6 5.0 7.0 1.0 3.5 4.13 benchmark 0.4 5.0 7.0 3.5 6.0 5.38 cont.64 0.6 1.0 4.5 1.0 1.0 1.8 cont.64 0.4 1.0 5.0 1.0 2.5 2.38

Example M.

Similar biological activity is obtained from analogous compounds.

Example N

Herbicidal activity of 80bAM Compound Norm £ AB/bа Herbicidal activity according to the scale from 1 to 9 at 8ΟΙ.ΑΜ Compound 64 300 2.7

200 5.7

100 6.7

Example Ο

Herbicidal activity against millet weeds

Sit down Product Herbicidal activity in % not us ka/la EHSSS 5ETSJ PANMI Average

benchmark 0.5 0.75 10.3 26.9 44.2 44.3 0 0 18.17 23.7 connection 64 1,125 64.7 49.5 26.7 46.97 1,688 72.1 63.5 65.6 67.1

In all tests, compound 64 gave better results than the standard.

Example R. Compound- Norm £ AB/bа Herbicidal activity according to the scale 1-9 δΟίΝΙ ΣΝΕΡ1 ΜΕΚΑΝ ΑΜΑΚΕ Average

benchmark 300 1.3 2.9 1.3 2.4 1.98 cont.57 300 1.0 3.1 1.0 1.1 1.55 cont.59 300 1.0 2.9 1.0 1.0 1.48 joint 100 300 1.0 2.9 1.3 1.1 1.58 cont.62 300 1.0 3.9 1.0 2.4 2.1 cont.63 300 1.0 3.0 1.0 2.6 1.9 cont.64 300 1.0 2.7 1.1 2.7 1.88

Example ρ

compound- Norm £ AB/bа ANTAK Herbicidal activity according to ΟΕΝΑΚ scale from 1 to 9 BARSO SAYAAR Medium benchmark 300 1.3 2.2 1.1 2.1 1.68 cont.9 300 1.0 2.7 1.0 2.0 1.68 cont.10 300 1.0 2.6 1.0 2.1 1.68 cont.11 300 1.0 2.6 1.0 2.0 1.65 Example K Join- Norm Herbicidal activity according to knowledge £ AB/bа scale from 1 to 9 ANTAK SEIAC BARSO SAYAAR Medium benchmark 200 1.0 2.4 1.7 2.0 1.78 cont.5 200 1.0 3.0 1.3 2.0 1.83 Example 5 Join- Norm Herbicidal activity according to knowledge £ AB/bа scale from 1 to 9 ANTAK ΟΕΝΑΚ BARSO SAYAAR Medium benchmark 1000 1.1 5.0 1.3 2.0 2.35 cont.99 500 ι,ο 1.9 1.0 3.7 1.9 Example T Join- Norm Herbicidal activity according to knowledge £ AB/bа scale from 1 to 9 ANTAKOENAK BARSO SAYAAR Medium benchmark 500 1.3 2.7 2.2 1.4 1.9 cont.36 500 1.0 2.8 2.4 1.0 1.8 cont.22 500 1.0 3.2 1.0 2.3 1.88 cont.5 500 1.0 3.3 1.0 2.3 1.9

Example and

Connect- Norma

Herbicidal activity according to

knowledge £ AB/bа scale from 1 to 9 Medium ANTAK SEMC BARSO SAYAAR benchmark 750 3.9 5.3 2.9 2.9 3.75 cont.54 750 2.7 2.9 2.7 3.5 2.95 cont.53 750 2.6 4.7 2.8 4.3 3.6

Patent claims physiologically tolerable salts by plants.

Claims (4)

Patent claims physiologically tolerable salts by plants. 1. Herbicidal agent, characterized in that it contains as active ingredient at least one compound of general formula 1 Kz in which K ₁ represents a hydroxy, halogen, cyano, nitro, amino group, a straight-chain or cyclic alkyl group having 1 to 6 carbon atoms, which is optionally substituted by halogen, a straight-chain or branched-chain alkoxy group having 1 to 4 carbon atoms, a phenoxy group, a methylthio or methylsulfonyl group; K ₂ represents halogen, nitro, methyl or methoxy, η represents 1 or 2, m represents 0 or 1, wherein the sum of η and m is equal to 1, 2 or 3, K ₃ means hydroxy or halogen, or a group of the formula -OC/O/1H/CH ₃ / ₂ or OC/O/ΖΚρ in which K ₄ represents a straight-chain alkyl group of 3 to 12 carbon atoms, a branched alkyl group of 4 to 7 carbon atoms, a cyclohexyl group, phenylethyl or phenyl; Ζ means a single bond, oxygen or sulfur, and X stands for halogen, as do its 2. Herbicidal agent according to claim 1, characterized in that it contains at least one compound of formula I, in which means halogen, alkyl is 1 to 4 carbon atoms, which can optionally be substituted multiple times by halogen, a straight-chain or branched-chain alkoxy group with 1 to 4 carbon atoms and η+m means one of the numbers 1 or 2; or K ₁ means a cyclohexyl residue and K ₂ means a halogen atom, a methyl or a methoxy group, and η+n means the number 1, K ₃ means the residue Οΰ/Ο/ΖΚ ₄ , in which K ₄ and Ζ have the meanings specified in claim 1 and X means chlorine or bromine, as well as its salts physiologically tolerated by plants. 3. Herbicidal agent according to claim 1, characterized in that it contains at least one compound of formula I, in which K, and independently of each other denote chlorine or fluorine and η+m denotes 1 or 2 or K ₁ and K ₂ denote trifluoromethyl, and n+m denotes 1, K ₃ denotes the group OC/O/ΖΚ,, in which K ₄ and Ζ have the meanings specified in claim 1 and X denotes bromine or chlorine. 4. A method for controlling weeds, characterized in that a compound of formula I, in which K ₍ , Kp K ₃ , X, η and m have the meanings specified in claim 1, is allowed to act on the weeds or their environment.